Ultragenyx Pharmaceutical (RARE) shares fell for a second consecutive day on Tuesday, August 18th. Investors are awaiting an FDA decision on DTX401, a gene therapy for glycogen storage disease type Ia (GSDIa). The agency established a PDUFA action date of August 23, 2026.
DTX401 would be the first treatment to address the underlying genetic cause of GSDIa. Patients currently manage the disorder by consuming cornstarch frequently to maintain safe blood sugar levels. The FDA is reviewing the application under Priority Review status.
The upcoming decision represents a significant catalyst for the company’s product pipeline. Ultragenyx also expects a PDUFA action date for its UX111 drug on September 19.